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Conservation Act of 1980 (ANILCA, 1980) requires the Secretary of Interior to conduct a continuing study of fish, wildlife, and habitats on the Innoko National Wildlife Refuge (INWR). Included in this study is a determination of the extent, location, and carrying capacity of fish and wildlife habitats....

No abstract available....

Late Quaternary calderas have been identified at 12 of 40 volcanic centers in the eastern Aleutian arc, and sufficient radiocarbon dates and geologic information have now been obtained to either date or constrain the timing of the climactic caldera-forming eruptions. At least eight major caldera-forming events, each characterized by estimated...

No abstract available....

Title III of the Alaska National Interest Lands Conservation Act (ANILCA, 1980) established the Yukon Flats National Wildlife Refuge (YFNWR). Section 304 of the Act requires the Secretary of Interior to "prepare, and from time to time revise, a comprehensive conservation plan" for the refuge. Before developing a plan for...

Abundant skeletal remains demonstrate that lambeosaurine hadrosaurid, tyrannosaurid, and troodontid dinosaurs lived on the Alaskan North Slope during late Campanian—early Maestrichtian time (about 66 to 76 million years ago) in a deltaic environment dominated by herbaceous vegetation. The high ground terrestrial plant community was a mild- to cold-temperate forest composed...

In 1985, the U.S. Geological Survey initiated a research program to produce 1:250,000-scale land cover maps of Alaska using digital Landsat multispectral scanner data and ancillary data and to evaluate the potential of establishing a statewide land cover mapping program using this approach. The geometrically corrected and resampled Landsat...

No abstract available....

Fragments of Late Proterozoic ocean crust and mantle (ophiolites) occur within six major fault zones that mark sutures between crustal blocks (microplates) that were accreted between about 630 and 715 Ma to form the Arabian Shield. We report new U-Pb zircon ages for ophiolitic gabbro, diorite, and plagiogranite that range...

The crustal structure beneath the exposed terranes of southern Alaska has been explored using coincident seismic refraction and reflection profiling. A wide-angle reflector at 8-9 km depth, at the base of an inferred low-velocity zone, underlies the Peninsular and Chugach terranes, appears to truncate their boundary, and may represent...

Cretaceous floras in Alaska, when compared to those at mid-latitudes, generally indicate later appearances in Alaska of major clades and major leaf morphologies. Compared to mid-latitude floras, Alaskan Late Cretaceous floras contain few major clades. The Alaskan clades diversified but at a low taxonomic level. Migrational pathways into high latitudes were probably along streams. Similar patterns characterized the Alaskan Tertiary, although some...

This study was conducted as a part of the U.s. Geological Survey's Earthquake Hazards Reduction Program. The goal of this program is a reduction of earthquake hazards through the incorporation of research findings on these hazards into land-use planning decisions. An important objective of the Earthquake Hazards Reduction Program is...

Common lead isotopic compositions have been determined on feldspars from meta-igneous rocks from nine tectono-stratigraphic terranes or subterranes in east-central Alaska. Most of the terranes have distinct and well-defined signatures in terms of isotopic composition; thus, most can be distinguished on conventional...

No abstract available....

The population dynamics of Northern Fulmars (Fulmarus glacialis) were studied at the Semidi Islands in the western Gulf of Alaska. Fulmars occurred in a broad range of color phases, and annual survival was estimated from the return of birds in the rarer plumage classes. A raw estimate of mean annual...

Interspecific aggression in waterfowl (Anatidae) is relatively common (McKinney 1965; Kear 1972; Savard 1982, 1984), but interactions leading to mortality of one of the combatants are rarely-observed in the wild. A recent debate (Livezey and Humphrey 1985a, 1985b; Nuechterlein and Storer 1985a, 1985b; Murray 1985) has centered on the proximate...

The causes and effects of the oceanographic and atmospheric phenomena known as El Nino and the Southern Oscillation (ENSO) have been studied intensively in recent years (Cane 1983, Rasmusson and Wallace 1983, Barber and Chave 1983, Cane and Zebiak 1985). ENSOs occur at semiregular intervals of 3-4 years, and the...

This book was written 'to provide an up-to-date data bank from which those wishing to construct models concerned with the evolution of Africa .... can draw.' As such, it attempts a survey of 'integrated geology and geochronology' of the African continent throughout the Precambrian and into the Phanerozoic. Political and...

No abstract available....

Summer surveys of the incidental catch of marine birds and mammals in fishing nets around the east coast of Newfoundland indicated that over 100 000 animals were killed in nets during a 4-year period (1981–1984). Composition of catches depended on foraging behaviour, regional abundance, and the degree of foraging aggregation...

Observations of three incidents of the mass mortality of nearshore fishes are reported; each corresponded to periods of high-amplitude, long-period swells during the 1982-1983 El Niño event along the coast of central California. Members of the nearshore kelp forest fish assemblage, primarily of the genus Sebastes, accounted for 96%...

New data extend our understanding of the 1912 eruption, its backfilled vent complex at Novarupta, and magma-storage systems beneath adjacent stratovolcanoes. Initial Plinian rhyolite fallout is confined to a narrow downwind sector, and its maximum thickness may occur as far as 13 km from source. In contrast, the partly contemporaneous...

To investigate the possible relation between the fabric (microstructural arrangement of particles) of a fine-grained sedimentary deposit and the depositional and environmental processes of that deposit, the fabric of sediment samples from the sea floor of two different depositional settings, Shelikof Strait and...

A possible example of a very deep glacial excavation is provided by a distinctive gravity low located at the front of a valley glacier that once flowed into glacial Lake Aniuk (formerly Lake Noatak) in the western Brooks Range. Geologic and geophysical data suggest that sediments or ice filling a...